Method of operation of twin roll strip caster to reduce chatter

摘要

A method and apparatus for casting thin strip including assembling a pair of counter-rotating casting rolls forming a gap between the casting surfaces of the rolls at a nip between the rolls through which metal strip can be cast; assembling side dams adjacent end portions of the rolls to permit a casting pool of molten metal to be formed on the casting surfaces; counter-rotating the rolls such that the casting surfaces each travel inwardly toward the nip to form metal shells on the surfaces of the rolls and deliver a cast strip downwardly from the gap between the rolls with a mushy internal portion; and providing a drive mechanism to oscillate the gap amplitude between the casting rolls between ±5 and ±50 microns at a frequency between 1 and 7 hertz to vary thickness of the mushy internal portion in the cast strip and reduce chatter during casting.